<?php
namespace TYPO3\CMS\Core\Cache\Backend;

/*                                                                        *
 * This script belongs to the FLOW3 framework.                            *
 *                                                                        *
 * It is free software; you can redistribute it and/or modify it under    *
 * the terms of the GNU Lesser General Public License, either version 3   *
 * of the License, or (at your option) any later version.                 *
 *                                                                        *
 * The TYPO3 project - inspiring people to share!                         *
 *                                                                        */
/**
 * A contract for a cache backend which supports tagging.
 *
 * @api
 */
interface TaggableBackendInterface extends \TYPO3\CMS\Core\Cache\Backend\BackendInterface
{
    /**
     * Removes all cache entries of this cache which are tagged by the specified tag.
     *
     * @param string $tag The tag the entries must have
     * @return void
     * @api
     */
    public function flushByTag($tag);

    /**
     * Finds and returns all cache entry identifiers which are tagged by the
     * specified tag
     *
     * @param string $tag The tag to search for
     * @return array An array with identifiers of all matching entries. An empty array if no entries matched
     * @api
     */
    public function findIdentifiersByTag($tag);
}
